Translation of abstract (English)

The aim of the present study was the construction and evaluation of a student admission test for the subject of Psychology at the University of Heidelberg in the context of the reform of the general university selection law (see Reich, 2002) which intends greater autonomy of universities in respect to the selection of applicants for university places. Based on a work analysis, subject-specific cognitive ability tests were designed and construct evaluated in accordance with Rasch model requirements with a total sample of N = 434 students from different subjects. The resulting tests were first examined regarding their subject-specific discrimination power between first semester student samples from different subjects. The central criterion validity hypothesis of this study was that a substantial improvement in the prediction accuracy of success in the form of grades would be obtained by combining the results from cognitive tests to the average grade of the "Abitur" certificate in multiple regression analyses (so-called incremental validity). In addition, the stability of criterion validities of personality questionnaires was analysed in relation to very probably faked responses in a selection context. For this condition, one half of the study participants was instructed to present themselves as positively as possible in their responses to the personality questionnaires (Faking good), whereas the respondents to the other half of the personality questionnaires received no such instruction. The test battery obtained only satisfactory results in terms of subject-specific discrimination power after controlling statistically for the "Abitur" grade. Including the test results with the "Abitur" grade in multiple regression analyses increased the predictive validity only slightly with three of four criteria. Moreover, the regression analysis results proved unstable in cross validations. The analyses of the validity of personality questionnaires under experimentally induced faked responses showed that criterion validities observed under the normal instruction decreased to insignificance under the faking-good instruction condition. Generally, this effect was not explainable by possible correlation-reducing variance differences between the scale raw scores of both instruction versions. In summary, the main results of this study confirmed past findings, which show the "Abitur" grade as the best predictor for study success (see e.g. Baron Boldt, 1989). This conclusion is discussed in relation to the utility of incremental validity as an evaluation standard in respect to selection decisions. Finally it is argued that tests should be evaluated on the basis of correct classification rates (so-called true positives and true negatives) while taking base rates into account (Schonemann & Thomson, 1996; Schonemann, 1997).